Quasi-Fourier-transform limited, scannable, high energy titanium-sapphire laser source for high resolution spectroscopy

A tunable injection seeded Ti:sapphire laser source has been developed and tested. Slave-master tandem cavity and ramp-lock-and-fire concepts have been implemented and fully controlled by a digital signal processor. A Fourier-transform-based analysis, as well as direct measurements, have demonstrated spectral linewidths in the range of 3.5-15 MHz (HWHM), with potential tunability over the entire Ti:sapphire lasing range. A quasi-Fourier-transform limited spectral linewidth is demonstrated assuming a secant hyperbolic shape of the electromagnetic field. Output energies > 100 mJ have been reached with similar to 300 mJ of pump energy. The highest spectral purity is obtained using the quadruple pumping scheme.